JPH0633767B2 - Slurry pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slurry pump for concrete, mortar, various slurries and the like.

A conventional example of a slurry pump will be described. Conventionally, a hydraulic circuit of a hydraulically driven piston piston slurry pump is an open circuit system using a one-way discharge type hydraulic pump. As shown in FIG. Cylinder
(a) A one-way discharge type hydraulic pump (c) is used in the drive hydraulic circuit for the main hydraulic cylinders (b) and (b) that are connected to each of (a) and (a). A relief valve (d) is provided on the discharge side, and a mechanism in which a hydraulic switching valve (e), a main hydraulic cylinder switching valve (f), a valve driving switching valve (g), etc. are interposed is provided. A hydraulic switching valve (e) is installed between the main hydraulic cylinders (b) and (b) of the pump and the pump, and the main hydraulic pressure is controlled to control the operating direction of the hydraulic piston of the main hydraulic cylinders (b) and (b). The switching valve (f) for the silane is becoming indispensable. For this reason, the number of parts is increased, and since the conventional hydraulic circuit generally has a large flow rate, the size of the switching valve is also increased, resulting in a significant increase in cost and weight, pressure loss, vibration during switching, noise, etc. Also has the drawback of becoming larger.

The present invention is a slurry pump developed in view of the above circumstances, in which a main hydraulic cylinder is connected to each of a pair of slurry pump cylinders, and a main circuit between the main hydraulic cylinders is closed by a main hydraulic pipe. And a single reversible discharge type main hydraulic pump is provided in the main hydraulic pipe, and a branch pipe is provided which is branched from the main hydraulic pipe and communicates with a valve drive cylinder. A valve drive switching valve is installed in the middle of
It is characterized in that the discharge direction of the variable displacement hydraulic pump is reversed after the valve drive cylinder is activated, and the purpose is to reduce the pressure of the main hydraulic pipe connected to the main hydraulic cylinder. By switching the oil flow by reversible switching of the main hydraulic pump, a switching valve in the main hydraulic pipe is unnecessary, and a slurry pump in which the above-mentioned drawbacks are eliminated is provided.

The present invention has the above-mentioned configuration, wherein a main hydraulic cylinder is connected to each of a pair of slurry pump cylinders, and the main hydraulic cylinders are connected by a main hydraulic pipe in a closed circuit. One reversible discharge type main hydraulic pump is interposed between the main hydraulic pump and the direction of pressure oil discharge of the main hydraulic pump by a signal generated by switching the intake valve or the discharge valve. Since the switching is performed, it is not necessary to provide a switching valve in the main hydraulic pipe between the main hydraulic pump and the both main hydraulic cylinders, the pressure loss in the main hydraulic pipe is significantly reduced, and the driving force is increased as the hydraulic pressure increases. The pump drive efficiency is significantly improved and the main hydraulic cylinder hydraulic circuit and valve drive cylinder hydraulic circuit are driven by the same hydraulic pump. Drives the valve drive cylinder at the time of the completion can be realized cheaper cost fewer components rotating structure becomes simple because so as to reverse the discharge direction of the hydraulic pump after the operation of the valve drive cylinder has been completed.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 shows an embodiment of the present invention, in which (5a) (5b)
Is a pair of slurry pump cylinders, and (6) is driven by a pair of valve driving silanes (6a) and (6b) so as to be alternately positioned on the tip side of the pair of slurry pump cylinders (5a) and (5b). Suction valve, (7) is a pair of valve drive cylinders (7a) (7b)
Accordingly, the discharge valve is driven so as to be alternately located on the tip side of the slurry pump cylinders (5a), (5b) and alternate with the suction valve (6). The pair of slurry pump cylinders
Main hydraulic cylinders (10a) and (10b) are connected to each of (5a) and (5b), and main hydraulic pipes (11a) and (11b) are provided on the piston head side of each of the main hydraulic cylinders (10a) and (10b). And the piston rod side of the main hydraulic cylinders (10a) and (10b) are connected by the communication pipe 101 to fill oil to form a closed circuit, and the main hydraulic pipes (11a) and (11b) are reversible. It has a structure in which a discharge type main hydraulic pump (1) is interposed.

This constitutes a closed circuit from one main hydraulic cylinder (10a) through the main hydraulic pipe (11a), the main hydraulic pump (1), the main hydraulic pipe (11b) to the other main hydraulic cylinder.

More specifically, the hydraulic piston (101a) of the main hydraulic cylinder (10a) is a slurry pump cylinder via a rod.
Connected to slurry piston (501a) of (5a), main hydraulic piping
When pressure oil is supplied from (11a), the main hydraulic cylinder (10a) moves the slurry piston (501a) to the right side in the drawing, so that the slurry pump cylinder (5a) is in the discharge stroke. At this time, the oil on the piston rod side of the main hydraulic cylinder (10a) is moved to the piston rod side of the main hydraulic cylinder (10b) via the communication pipe (101) by moving the hydraulic piston (101a) to the right side in the figure. Therefore, the hydraulic piston (101b) of the main hydraulic cylinder (10b) moves to the left side in the figure, and the slurry piston (5
01b) will also move to the left side of the figure. As a result, a suction stroke for sucking the slurry into the slurry pump cylinder (5b) is performed.

At this time, the hydraulic piston (101b) of the main hydraulic cylinder (10b)
By moving b) to the left side of the figure, the oil on the piston head side of the main hydraulic cylinder (10b) is discharged through the main hydraulic pipe (11b) .At this time, the main hydraulic pressure of the main hydraulic pump (1) Plumbing (11b)
Since the side is the suction side of the main hydraulic pump (1), the total amount of oil discharged is sucked into the main hydraulic pump (1) and pressurized by the main hydraulic pump (1), It will be discharged to (11a).

On the contrary, when pressure oil is discharged from the main hydraulic pump (1) to the main hydraulic pipe (11b), the operation is exactly the opposite, and the hydraulic piston (101b) and the slurry piston (501b) move to the right of the figure. By moving in the direction, the slurry sucked in the slurry pump cylinder (5b) in the previous process is pushed out to the slurry transport pipeline (30) through the discharge port (701b). At this time, in the main hydraulic cylinder (10a), oil moves from the piston rod side of the main hydraulic cylinder (10b) to the piston rod side via the communication pipe (101), and the hydraulic piston (101a) moves to the left in the figure. The slurry piston (501a) also moves to the left as it moves to the slurry pump cylinder.
A suction stroke for sucking the slurry into (5a) is performed. The oil discharged from the piston head side of the main hydraulic cylinder (10a) by moving the hydraulic piston (101a) to the left is sucked into the main hydraulic pump (1) via the main hydraulic pipe (11a), It is pressurized by the main hydraulic pump (1) and discharged to the main hydraulic pipe (11b).

It should be noted that the suction port (601a or 601b) of the slurry pump cylinder during the suction process is opened and the discharge port (701a) is opened with respect to the suction process or the discharge process of the slurry pump cylinders (5a) and (5b).
, Or 701b) is closed by the discharge valve (7) (that is, the other slurry pump cylinder is in the discharge stroke, the suction port is closed by the suction valve (6), and the discharge port is open).
The state is called pressure feeding operation (that is, the slurry is sucked from the suction port to one slurry pump cylinder and the slurry pump is pushed from the other slurry pump cylinder to the slurry transport pipeline (30) through the discharge port) ,
In the suction stroke of the slurry pump cylinder, the suction port (601a,
Or 601b) is closed and the discharge port (701a or 701b) is opened (that is, the other slurry pump cylinder is in the discharge stroke, the suction port is opened, and the discharge port is closed by the discharge valve (7)). ) Reverse operation (that is, the slurry is sucked from the slurry transport pipeline (30) to the slurry pump cylinder on one side through the discharge port, and then to the hopper (not shown) from the slurry pump cylinder on the other side through the suction port. Return).

Also, an auxiliary hydraulic pump (20) having a relief valve (21) is connected to the main hydraulic pipes (11a) (11b) via check valves (22) (22),
A shuttle valve (23) is provided between the main hydraulic pipes (11a) and (11b) and is connected to the tank via the shuttle valve (23) via a relief valve (24). Branch pipes (25a) (25) branched from the main hydraulic pipes (11a) (11b) to the valve drive cylinders (6a) (6b), (7a) (7b)
An electromagnetic solenoid valve drive switching valve (26) is installed in b), and a hydraulic piston position detector () is provided near the stroke end (right end in the figure) of the main hydraulic cylinders (10a), (10b). 27a) and (27b) are attached and emit an electric signal when the hydraulic piston reaches the stroke end. Further, as shown in FIG. 2, a valve drive cylinder piston position detector (2) is provided near the rod side slack end of the valve drive cylinders (7a), (7b).
8a) and (28b) are attached, and an electric signal is emitted when the piston of the valve drive cylinder reaches the stroke end.

The illustrated embodiment of the present invention has the above-mentioned structure, and its function and effect will be described. In FIG. 2, the discharge side of the main hydraulic pump (1) is connected to the main hydraulic pipe (11a). And the main hydraulic pipe (11b) side becomes the suction side of the main hydraulic pump (1), and the hydraulic piston (101a) is sucked into the slurry pump cylinder (5a) during the discharge stroke in which it moves forward with the slurry piston (501a) to the right side in the figure. The slurry that had been discharged is discharged to the right side in the figure. On the other hand, the hydraulic piston (101b) is moved by the oil on the piston rod side of the main hydraulic cylinder (10a) to the piston rod side of the main hydraulic cylinder (10b) via the communication pipe (101), and thus the slurry piston (501b). ), The slurry pump cylinder (5b) sucks the slurry into the slurry pump cylinder (5b) during the suction stroke.

Next, the hydraulic piston (101a) moves to the stroke end (second
Hydraulic piston position detector (27a)
The valve drive switching valve (26) is energized by the signal generated from the valve drive switching valve (26) to switch to the state shown in FIG. 2a, the intake valve (6) and the discharge valve (7) are switched, and the discharge valve (7) is switched. ) Is switched from the slurry pump cylinder (5b) side to the same (5a) side in the figure, the energization of the valve driver exchange valve (26) is stopped by a signal emitted from the valve drive cylinder piston position detector (28b). , The valve drive switching valve (26) returns to the neutral state (the lower side of the valve symbol in the illustrated example), and at the same time, the signal from the valve drive cylinder piston position detector (28b) causes the main hydraulic pump (1) to move. The tilt angle switches to the opposite side and the pressure oil discharge direction of the main hydraulic pump (1) is reversed, and the main hydraulic pipe (11b) becomes the discharge side and the main hydraulic pipe (11a) becomes the suction side. The main hydraulic pump
The hydraulic piston (101b) that has reached the left end in the figure due to the reversal of the discharge direction in (1) starts moving to the right side in the figure together with the slurry piston (501b), and
The discharge stroke of b) is performed. When the hydraulic piston (101b) moves and reaches the right end in the figure, the hydraulic piston position detector (27
b) is activated to generate a signal, the valve drive switching valve (26) is energized to switch (to the upper side of the symbol shown in the figure), and the intake valve
In the figure, (6) shows the slurry pump cylinder (5b) side to (5a) side, the discharge valve (7) is the slurry pump cylinder (5a)
Side to (5b) side, the valve drive cylinder piston position detector (28a) operates and emits a signal, whereby the valve drive changeover valve (26) is de-energized and the valve drive changeover valve (26) ) Returns to the neutral state (the lower side of the symbol in the example shown), and at the same time, the tilt angle of the main hydraulic pump (1) is switched to the opposite side in the same way as described above, and the pressure oil discharge direction of the main hydraulic pump (1) The main hydraulic piping (11a) is replaced by the hydraulic piping pump (1).
The stroke on the discharge side of starts. The pressure pumping operation of the slurry pump is performed by repeating the above steps.

As described above, in the pumping operation, the valve drive switching valve (26)
Is in the non-energized state (that is, the neutral state = the lower symbol in the figure) while the hydraulic pistons (101a and 101b) are moving, and the hydraulic piston (101a or 101b) reaches the stroke end (the right end in the figure) and sucks. Power was supplied when the valve (6) and discharge valve (7) were switched, but during reverse operation, the hydraulic piston (101
Energized during movement of a and 101b) (Fig. 2b), suction valve
When switching (6) and the discharge valve (7), it is made to be in a non-energized state (Fig. 2c). The conversion between the pressure feeding operation and the reverse rotation operation can be configured by an ordinary electric circuit, and thus the description thereof will be omitted.

Now, suppose that the discharge side of the main hydraulic pump (1) is the main hydraulic pipe (11b).
The reverse operation will be described assuming that the main hydraulic pipe (11a) is on the suction side of the main hydraulic pump (1) (second b).
(Fig.), The hydraulic piston (101b) moves to the right in the figure, but since the valve drive switching valve (26) is energized at that time, the suction valve (6) is placed on the side of the slurry pump cylinder (5a) and the discharge valve (5a). 7) is
It has been switched to the (5b) side, and the hydraulic piston (101
Along with the rightward movement of b), the slurry in the slurry pump cylinder (5b) passes through a suction port (601b) and a hopper (not shown).
Return to. On the other hand, in the slurry pump cylinder (5a), the slurry piston (501a) moves to the left, and the slurry in the slurry transport pipeline (30) is sucked into the slurry pump cylinder via the discharge port (701a). Hydraulic piston (101
When the right end of b) is reached, the hydraulic piston position detector (27b) is activated and a signal is transmitted, whereby the valve drive switching valve (26) is de-energized and the valve drive switching valve (26) is shown in the figure. It becomes the lower symbol (Fig. 2c), and the suction valve (6) and the discharge valve (7) are switched to opposite positions. When the discharge valve (7) is switched to the slurry pump cylinder (5a) side, the valve drive cylinder piston position detector (28b) operates and the signal causes the valve drive switching valve
(26) is energized again and returns to the upper symbol shown in the figure, and at the same time, the tilt angle of the main hydraulic pump (1) is switched to the opposite side and the pressure oil discharge direction of the main hydraulic pump (1) is reversed, Main hydraulic piping
(11a) becomes the discharge side of the main hydraulic pump (1), and the hydraulic piston (101a) that had moved to the left in the previous stroke starts moving to the right.

Similarly to the above, when the hydraulic piston (101a) reaches the right end and the hydraulic piston position detector (27a) operates and a signal is transmitted, the valve drive switching valve (26) is de-energized and the valve drive switching is performed. valve
(26) is a symbol on the lower side in the figure, the suction valve (6) is from the slurry pump cylinder (5b) to (5a) side, and the discharge valve (7) is (5).
Switching from (a) to (5b) side, the valve drive cylinder piston position detector (28a) is activated and a signal is transmitted, whereby the valve drive switching valve (26) is energized again and the upper symbol shown in the figure is displayed. At the same time, the tilt angle of the main hydraulic pump (1) is switched to the opposite side again, the pressure oil discharge direction of the main hydraulic pump (1) is reversed, and the stroke of moving the hydraulic piston (101b) to the right again again. Begins. By repeating the above, the reverse rotation operation is performed in which the slurry in the slurry transport pipeline (30) is sucked by the slurry pump cylinder and further returned to the hopper.

In the reverse operation by the conventional device, the main hydraulic pressure of the main hydraulic cylinder on the side that sucks the slurry in the slurry transport pipeline (30) into the slurry pump cylinder (the cylinder in which the slurry piston moves to the left in the figure). Piping is first
In the figure, the main hydraulic cylinder check valve (f) and the hydraulic check valve
If there is a head pressure in the slurry transportation pipeline (30) due to the fact that it is in direct communication with the oil tank via (e) and there is a rising part in the slurry transportation pipeline, etc., the slurry piston will be moved by the head pressure. When pushed back, the oil in the main hydraulic cylinder is returned to the oil tank as it is, so that there is no condition to hydraulically support the slurry piston, and the speed of the slurry piston is not controlled at a stroke to the left end. While moving, it violently collides with the stroke end and makes a large impact noise and vibration,
In some cases, the water hammer phenomenon may cause damage to the slurry transportation pipeline and the slurry pump.

However, according to the present invention, even in such reverse operation, the main hydraulic pipe (11
a) or (11b) is connected to the suction side of the hydraulic pump (1), and the main hydraulic cylinder (10a) or (10b) is connected to the main hydraulic pump.
Since the hydraulic circuit up to (1) is completely sealed and does not directly communicate with the oil tank as in the conventional structure, the slurry piston (501a) or (501b) has a slurry transport pipeline (30). Even if the head pressure of the main hydraulic cylinder is applied, the main hydraulic pump (1) causes the main hydraulic cylinder (10a) to pass through the main hydraulic pressure (11a) or (11b).
Since the amount of oil discharged from a) or (10b) is regulated,
The hydraulically applied brake prevents the slurry piston (501a) or (501b) from self-propelling.

Further, as shown in FIG. 3, the operation time chart in each mechanism of the pressure feeding operation stroke is the forward movement of the slurry piston (501a), that is, the discharge stroke (I), the changeover stroke of the suction valve (6) and the discharge valve (7) ( II), the forward stroke of the slurry piston (501b), that is, the discharge stroke (III), the switching stroke (IV) of the suction valve (6) and the discharge valve (7), the main hydraulic pipe (11a) side by the main hydraulic pump (1) The discharge to the (+) side is shown and the discharge to the main hydraulic piping (11b) side is shown in the (-) side shown to the (-) side, and the pulse signal from the hydraulic piston position detector (27a) is shown. (27'a) The pulse signal (27'b) from the hydraulic piston position detector (27b) is shown.
(B) is output, the switching operation of the valve drive switching valve (26) is as shown in (C), and the valve drive cylinder piston position detector (28a) and valve drive cylinder piston position detector
The pulse signals (28'a) and (28'b) emitted from (28b) are shown in (D).
As described above, the slurry pistons (501a) and (501b)
The suction stroke and the discharge stroke are continuously repeated alternately in reverse strokes, and the respective chart times are performed by an appropriate control mechanism not shown.

Also, during the above operation, the relief valve (24) is a shuttle valve.
The maximum discharge pressure of the main hydraulic pump (1) is controlled via (23), and the auxiliary hydraulic pump (20) plays a role of compensating the suction pressure of the main hydraulic pump (1). ).

Therefore, according to the above embodiment, the reversible discharge type main hydraulic pump (1) and the main hydraulic pipes (11a) (11b) between the main hydraulic cylinders (10a) and (10b) require no switching valve. Therefore, there is no pressure loss due to the conventional hydraulic switching valve, that is, the pressure loss in the main hydraulic piping (11a) (11b) is significantly reduced.
The hydraulic pressure supplied to the main hydraulic cylinders (10a) and (10b) will be greatly increased, which will reduce fuel consumption due to improved efficiency, suppression of hydraulic oil temperature rise, and even when switching the switching valve as in the past. Vibration and noise are eliminated, the start of the slurry piston is smooth, and the effect of reducing machine vibration and pulsation in the slurry transport pipeline is obtained.In the reverse operation, the main hydraulic pipe of the main hydraulic cylinder is directly connected to the main hydraulic pump. Since it is connected to the main hydraulic cylinder, the oil discharged from the main hydraulic cylinder directly becomes the suction pressure oil of the main hydraulic pump, so that the braking action works on the slurry piston, and the self-propelled operation of the slurry piston is prevented. With the above effect, the performance and reliability of the slurry pump are significantly improved.

In the embodiment, the piston rod side of the main hydraulic cylinders (10a) (10b) is connected by the communication pipe (101) to form a closed circuit.However, the piston head side is connected to form a closed circuit, and the main body is connected to the piston rod side. Even if the hydraulic pipes (11a) and (11b) are connected and the opposite piston rod side is connected, the basic idea does not change.

In the above embodiment, the auxiliary hydraulic pump (20) for compensating the suction pressure of the main hydraulic pump (1) is provided, but other agitators for the slurry pump, booms, auxiliary machinery, etc. It is also possible to use it, and the circuit composed of the relief valve (24) and the shuttle valve (23) that compensates for the maximum pressure of the main hydraulic pump (1) is not limited to the above circuit mechanism and various types are adopted In addition, the valve drive switching valve (26) with a similar function such as double-sided solenoid type, block center type, etc. can sufficiently achieve the purpose, and the valve drive cylinder piston position detector (28a) ( 28b) is not always necessary. For example, the elapsed time after actuation of the hydraulic piston position detectors (27a) (27b) (= intake valve
(6) and the discharge valve (7) after a lapse of time necessary for complete switching), set the discharge direction of the main hydraulic pump (1) and the valve drive switching valve (26) to an electrical timer, etc. It can also be controlled using. Further, although the slurry pump has been mainly described in the above, the present invention is not limited to this and can be applied to hydraulically driven piston type pumps for liquid, earth and sand, and the like.

Thus, according to the present invention, a main hydraulic cylinder is connected to each of the pair of slurry pump cylinders, the main hydraulic cylinders are connected by a main hydraulic pipe in a closed circuit, and the main hydraulic pipes are connected between the main hydraulic pipes. A single reversible discharge type main hydraulic pump is provided, a branch pipe that branches from the main hydraulic pump and communicates with a valve drive cylinder is provided, and a valve drive switching valve is provided in the middle of the branch pipe. Since the discharge direction of the variable displacement hydraulic pump is reversed after the valve drive cylinder is activated by switching the valve drive switching valve, it is detected that the intake valve and the discharge valve have been switched. By switching the valve drive switching valve and reversing the discharge direction of the main hydraulic pump by the signal, the hydraulic switching valve (e) and the main hydraulic cylinder switching valve (f) as in the conventional one shown in FIG. ) Is unnecessary Apparatus is simplified so that the number of parts is reduced a considerably lower cost. Further, the pressure loss in the main hydraulic pipe is remarkably reduced, the driving force is greatly increased as the hydraulic pressure increases, and the pump driving efficiency is remarkably improved.

Although the present invention has been described with reference to the embodiments, the present invention is of course not limited to such embodiments, and various design modifications can be made without departing from the spirit of the present invention. .

[Brief description of drawings]

FIG. 1 is a mechanism diagram of a conventional slurry pump, FIG. 2 and FIG.
FIGS. a, 2b and 2c are mechanical views showing an embodiment of the present invention, and FIG. 3 is a flow chart of FIG. 1: Main hydraulic pump, 5a, 5b: Slurry pump cylinder, 10a, 10b: Main hydraulic cylinder, 11a, 11b: Main hydraulic pipe,
101a, 101b: hydraulic pistons, 501a, 501b: slurry pistons.

Claims (1)

[Claims] 1. A main hydraulic cylinder is connected to each of a pair of slurry pump cylinders, and pressure oil acting on a hydraulic piston of the main hydraulic cylinder is supplied to and discharged from the main hydraulic cylinder to the slurry pump cylinder. In a slurry pump configured to suck and discharge slurry, a pair of main hydraulic cylinders are connected by a main hydraulic pipe in a closed circuit, and one reversible discharge type is provided in the main hydraulic pipe. A variable displacement hydraulic pump is provided, a branch pipe is provided that branches from the main hydraulic pipe and communicates with a valve drive cylinder, and a valve drive switching valve is provided in the middle of the branch pipe. The slurry pump is configured such that the discharge direction of the variable displacement hydraulic pump is reversed after the valve drive cylinder is activated by switching the above.